Method and apparatus for localizing mine explosions and fires.



2 SILEETS-SHEET I.

' Patented Apr. 9,1918.

gwve'nfoz elffoznag:

S. GRASTY 5L W. S. RODMANA APPLICATION men AUG. 25. 1914.

METHOD AND APPARATUS FOR LOCA'LIZING MINE EXPLUSlO-NS AND FIRES.

I. S. GRASTY & W'. S. RODMAN.

METHOD AND APPARATUS FOR LOCALIZ'ING MINE EXPLOSIONS AND FIRES. APPLICATION FILED AUG 25,1914.

1,261,924. Patented-Apr. 9, 1918.

2 SHEETS-SHEET 2 .D J: .1 '4 E L 7 C i Snow Life's;

attorney:

. To all whom it mcyconccm:

i and State of Virginia, I and WALTER 2 was SHARSHALL enA'srY-nNn i if VIRGINIA.

Be it known that we, J OHNI S H AItS iI ALL GRASTY, a citizen of the Unlted vStates, residing at University, county. of .Albemarle,

1 DON Ron Ama citizenof theUnited States,

i distance, upon the occurrencef of an explosion ad]acent to such closing means, the closing means belng of such a nature thatthe explosion itself, these s point 35.

and resident of the same place, haveinventwed certain newand useful. Improvements in Methods and Apparatus for Local zing Mine Explosions and Fires, of which the following is a specification.

Our inventionhas for its object toypro- Vide asystem of barriers for the,localiza-, tion ofmine-explosions, and of fires result-- ing therefrom, by placing atsuitable points in the mine, screens or permittingthe passage of the pressure, due

to explosion, Wlll check the .passage of the creens orbarriers be .ing ofsuch acharacter thattheyare normally outof the way, but are automatlcally interposedinthe passageor air-tunnels upon the. occurrence of an explos1on, andin1 time, tointercept the advancing way of'the explo ,sion alongsuch passage. Forthese purposes, it consists of suitable screens ,ofwiregauze, used n groups, with means .for 1 preferably automatically closingsuch screensfrom a time of actlonthereof is less than that taken for the travel of the explosion from the where closing means arelocated in to the screen. Inasmuch as thepropagation of 116,8XP10S1O11S is extremelyrapid', thisyrether consists in the. construction, combination and arrangementof the several partsof quires that the closing apparatus have a shortvtime constant. The invention fur-,

which it'is composed, which will be hereinafter more fully described and claimed.

Referring to the accompanying drawings in which corresponding parts are designated c v c of about two inches between each of the by corresponding mark of reference,:-

Figure 1 is a typical .reprfisentation'of a 4 mine having our invention applied thereto.

, Fig. 2 is anelevationof one of the barriers used, therein.

Specification of Letters Patent. ,Application filed ugust 25,1914. S eria1No.858,54=5.

SHEL

barriers which, while.

Patented Apr. 9, 1918.

- Fig. 3 is a section through the barrier shown in Fig. 2. V

Fig. 4 isan elevation of the barrier-release whichmay be employed.

. Fig. 5 is a plan view thereof.

Fig. 6 is a wire diagram. I Incarrying out our invention, the barriers A are located at suitable pointsin the passage-ways of the mine to be protected, such .barriers being normally held opened by electricallycontrolled mechanism, the circuit-controllers C for whichare locatedin the mine atpoints where explosions are liable, and against which explosions it is desired to protect. In practice, this distance should not be l ss than two hundred feet from the barriersto be controlled thereby so that upon an occurrence of, an explosion adjacentto any .of. the circuit-controllers,

the barrier or barriers controlled' thereby.

. will. be dropped across the passage-ways.

The barriers Afintheir most; perfected form, comprise suitable pivoted frames 1, preferably of iron, adapted to fitwithin casings 2 anchored in the passage-ways. These gcasings are, by preference, asnear flush ras may be with the wallsof the passage-ways so .as-to reduce as much as possible, the surfaces retarding the flow of the air in frontof the explosive-waves, and the frames fit therein sufliciently tight to prevent the passage of flame between them.

[Theframes l carry screens 3 of fine-wire mesh. In Fig. 3, we have represented three such screens carried in a single frame As shown there,.the outerscreens are ofcopper or bronze wire, andare of about fifty-mesh,

while the central screen 3*, is of about 100.

mesh In Fig. 2, we have further shown these, outerscreens .as protected by a coarse wire-netting, in order to afford a support therefor and protect. thesame from flying fragments. V In the barrier shown in Figs. 2

WALTER SHELDON BODMAN, or-omvnnsrr and 3, there s, by preference, an interval ,casing 2,,and is normallymaintained in its raised position, and in the top of the pas sage-way, by means of a lip 9* on its lower edge engaging one end of the armature 5, which is tulcrumed on the anvil 6 hung from the roof of the passage-way, the opposite end of such armature being normally held down by the attractive pull of an electric- ;rnagnet 7. Thus, as lon as there is suilicient field of force surround the magnet,

tile frame will be held raised, while, upon the breaking of tie circuit energizing the electro-magnet, the barrier will fall, and the passage-way. lts movements in may be accelerz ted in any way that t desired. By pivoting the door on the si of the casing on which the explosion is liabl to occur, no mechanism will be needed to hold the door closed when lowered against the pressure or the advancing wave.

The winding of the electro-magnet 7 is in cluded in a control-system, in which is a circuit-controller C, located, as before stated, at some distance from the barrier. l he circuit-controller may take many forms. in the form of the invention shown herein, the circuits are closed circuits, and therefore the controllers are circuit breakers. They may be either fusible, thermostatic, or pressure actuated. Tl e fusible circuit breakers will be easily fusible links placed in the electriccircuit atsuch strategic points as may be necessary. The thermostatic and the pressure actuated controllers can be of the type now used in automatic fire-protection practice.

In Fig. 6, we have shown a wiring diagram. In the circuit a of that figure, there is a controller for the single barrier releaser shown therein. in circuit Z) there are two controllers for a single barrier releaser, and in circuit 0, there is a single controller for two barrier releasers, all of the several circuits being branched from the main lines D and is obvious that the location of the controllers and of the barriers and the association made between the several controllers and the barriers, is dependent upon the conditions of each installation, and will be determined by the engineer in view of those conditions, the essential point of our invention being the utilization of fine mesh screens to stop the passage of flame in explosions, In this connection, it is proper to observe that we have ascertained that the use of screens in tandem, such as we have here disclosed in Figs. 2 and 3, produce a markedly din erent result "from the use of a single screen, and this, although the screens are not placed in contact with each other, but are separated by an interval. Vi e are not at this time able to explain the reason for this beneficial effect of the separated screens in tandem, but we find that with an explosive mixture located. on both sides of nasheaathe barrier, as well as between the screens thereof, and an explosion taking place in the explosive mixture to one side or" the screen, such explosion is not communicated through the barrier, although with a single screen and an explosive mixture on each side thereof, the explosion to one side of the screen would be transmitted to the opposite side thereof. it appears as if the gases trapped between adjacent and non-contacting screens act as a barrier to the transmission therethrough of an explosion from one side to the other, and we particularly point out this feature as an important one of our invention. it will benoted that between the screens of fine mesh a dead air space is formed, that is to say, one having no communication with the outside of the barrier,

.save through the interstices of the screens.

Having thus described our invention what e claim and desire to secure by Letters atent is 1.. As a barrier against the propagation of an explosion in an explosive atmosphere, a plurality of screens arrangedin tandem in the path to be protected against the passage of the explosion through such atmos phere and out of contact with each other and having an air space between them.

52. As a barrier against the propagation of an explosion in an explosive atmosphere, a plurality of screens arranged in tandem in the path to be protected against the passage of the explosion through such atmosphere and out of contact with each other and having a closed air space between them.

3. In an apparatus of the character described, the combination with a passageway to be protected against the'propagation of an explosion through atmosphere contained therein, of a barrier located in such passage-way and separating the explosive atmosphere in such passageway on opposite sides thereof such barrier including a plurality of wire screens arranged in tandem and having a closed air space between them.

4:. In an apparatus of the character described, the combination with a passageway to be protected against the propagation of an explosion through an explosive atmosphere contained therein, of a barrier located in such passage-way, and separating it into compartments having no communication an explosive with each other except through such barrier, the barrier including a plurality of wire screens arranged in tandem in the passage with an air space between them.

5. in an apparatus of the character described, the combination with a passage way to be protected against the propagation of an explosion through an explosive atmosphere contained therein, of a barrier including a plurality of wire-screens arranged in tandem adapted to be moved into position to separate thepassage-Way into sections having no communication with each other,

except through such barrier, and means 10- thereof to move such barrier.

6. The hereinbefore described methodof arresting explosion of inflammable air in,

the passage Way of tunnel, which consists in interposing 1n the path of such explosion a film of the lnflammable air'contained between partitions of Wire netting extending entirely across the said passage.

In testimony whereof we hereunto aflix 15 our signatures in the presence of two Wit- HBSSGS.

JOHN SHARSHALL GRASTY. WALTER SHELDON RODMAN.

Witnesses to the signature of John Sharshall Grasty:

GEO. J. LEE, 7. J. W. MULLER. -Witnesses to the signature of Walter Sheldon Rodinan:

MILES F. TRUMMELL, S.H. Dress.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

